With the popularity of the Internet technology, Peer-to-Peer (P2P) applications prevail on the Internet. In a P2P system, a P2P program of a terminal is both a client and a server.
Numerous Internet users use P2P software to download and share files, and a majority of such files are video files and software characterized by a great file length. Therefore, the downloading of P2P files occupies a lot of network bandwidth. Moreover, the P2P software selects partner peers blindly to some extent, thus generating immense disorderly traffic and imposing a huge impact on the backbone network.
In addition, many contents in different download protocols are repetitive, thus generating more repetitive traffic. The massive repetitive traffic leads to network congestion, and deteriorates the Quality of Service (QoS) of other network applications such as web browse and email.
To reduce the impact caused by the P2P downloading onto the backbone network, a P2P cache technology is applied in the conventional art to control the P2P traffic. The P2P cache needs to perform deep packet inspection for each packet, specifically, match the mode of each packet, judge whether the packet has P2P features, and finally make a conclusion about whether the packet is a P2P packet. For example, the packets of the Bit-Torrent (BT) protocol generally carry a BitTorrent identifier. Therefore, the packets with a BitTorrent identifier may be determined as BT protocol packets. The P2P cache supports a specific P2P protocol (for example, eMule, BT, FastTrack and Gnutella), and buffers the transferred P2P packets locally. If packet analysis shows that other users are requesting the same packet, the packet is sent to such users directly, and thus the traffic across the edge network is reduced.
The defects of the conventional art may be: The P2P cache needs to perform deep packet inspection for all routed packets, thus affecting the response speed of the whole network to some extent. Moreover, some protocol encryption and spoofing technologies are generally applied to the P2P client currently so that it is difficult to filter the P2P packets. Therefore, the conventional art is not enough for relieving the impact caused by the P2P packets onto the backbone network.